How-To

Growing Collards

If you don’t live in the South, you might not see collards very often; they are a leafy, cool-weather vegetable very popular for cooked greens. However, growing collards can be done throughout the country. A relative of cabbage, broccoli, Brussels sprouts, kohlrabi, and kale, this upright, dark green, waxy plant is a little like a cabbage that doesn’t make a head. It is one of the most cold-hardy of all vegetables, able to withstand temperatures in the upper teens. In zone 8 and southward, collards often provide a harvest through the entire winter. You can plant them in spring and fall, although collards planted in fall gardens are favored because the leaves are sweeter when kissed by frost.

Soil, Planting, and Care

Set out spring plants 3 to 4 weeks before the last frost; in late summer, plant 6 to 8 weeks before the first frost for fall and winter harvests. Like all vegetables, collards like full sun, but they will tolerate partial shade as long as they get the equivalent of 4 to 5 hours of sun to bring out their full flavor. Plant in fertile soil because collards should grow fast to produce tender leaves. They need fertile, well-drained soil with a soil pH of 6.5 to 6.8 to discourage clubroot disease. To be sure about your soil pH, test the soil with a do-it-yourself kit, or by using your regional Cooperative Extension office.

Collards are easy to plant. Space them 18 to 24 inches apart. After planting, water and fertilize.

Collards like a nice, even supply of water. Water regularly, applying 1 to 1.5 inches of water per week if it doesn’t rain enough to equal that amount. You can measure the amount of water with a rain gauge left in the garden. Apply organic mulch such as compost, finely ground leaves, weed-free hay, or finely ground bark to keep the soil cool and moist and to keep down weeds. Mulching will also help keep the leaves clean.

Collards can be cooked so many ways—in soups, stews, stir-fries, and casseroles, just to name a few—that you'll want to grow a lot of them. image source: iStock.com

Cold-hardy collards are always better after frost sweetens their leaves. This makes them perfect for fall gardens. Image source: iStock/mschowe

Troubleshooting

Keep a soil pH of 6.5 to 6.8 to discourage clubroot disease. Although worst on cabbage, Brussels sprouts, and turnips, clubroot affects all members of the cabbage family. The best way to avoid problems is to keep the garden clean. Insects that like collards include cabbage loopers, slugs, imported cabbageworms, cabbage root maggots, aphids, and flea beetles. Disease problems include black leg, black rot, clubroot, and yellows. To prevent diseases from building up in the soil, don’t plant collards or other cole crops in the same spot each year. Rotate with a non-cole crop for 2 years before returning to the same spot.

Harvest and Storage

Harvest leaves when they are up to 10 inches long, dark green, and still young. Old leaves may be tough or stringy. Pick the lower leaves first, working your way up the plant. You can even harvest leaves when frozen in the garden, but be careful because the frozen plant is brittle. Of course, wash the leaves thoroughly before using them in collard greens recipes, because soil often clings to the undersides. Collard leaves will keep for several days in the refrigerator.

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Filling in around collards with other plants—such as the spinach, onions, flowers, and herbs in this raised bed—helps keep a bed or container looking fresh as you harvest the bottom leaves

As you harvest collard leaves from the bottom up, the lower stem will be bare, making the plant look tree-like. New leaves grow from the center through cool weather.

FAQs

When do collards taste the best?

Collards taste sweetest when they grow in cool weather, especially in the fall after the leaves have been touched by frost. Spring-planted collards will grow through summer but they taste stronger when they mature in the heat.

What is the best way to wash collards?

Fill the kitchen sink or a large bucket with cold water. Place collards in a large colander and dunk them several times. Gently shake the greens to remove excess water and blot them dry with a clean towel.

How and where do I store collards?

After collards have been rinsed and thoroughly dried, wrap them in paper towels and seal them in a plastic bag. Keep them in the refrigerator until needed. NOTE: Even slightly moist collards will rot quickly.